Thai people believe that reborn, since then some of them believe lying in the coffin would be like their re-born. So their bad deeds are buries behind.

It would sound scary "lying on the coffin." Since coffin is a kind of symbol of death, people might avoid coffin. Some Thai people, however, believe that sleeping in the coffin brings them good luck.

Most Thai people believe the reborn, it is one of the important concept in Buddhism. So some Thai people believe that lying in the coffin means they reborn and their bad deeds buried behind them. As also they believe it would extend their life, too.

People are in black clothes lying in the coffin, and the monk are telling sermon and prayers as if they are really death for approximately 5 minute. Their head is turn to west in the same directions as the sun is going down.